.ys-parallax,.parallax-wrap{
    position: absolute;
    top:0;
    left:0;
    right:0;
    bottom: 0;
    overflow: hidden;
}
.ys-parallax{
    display: none;
}
.ys-parallax:hover .parallax-arrow{
    display: block;
}
.parallax-arrow{
    display: none;
    position: absolute;
    width: 50px;
    height: 50px;
    line-height: 50px;
    text-align: center;
    background-color: rgba(0,0,0,0.4);
    border-radius: 50px;
    overflow: hidden;
}
.parallax-arrow .ys-icon{
    font-size: 50px;
    font-weight: bold;
    color:#fff
}
.parallax-arrow-left{
    top:50%;
    margin-top: -25px;
    left:30px;
}
.parallax-arrow-right{
    top:50%;
    margin-top: -25px;
    right:30px;
}